1. Field of the Invention
The invention relates to a connection device in a semiconductor device and a method for forming the connection, and more particularly, to a connection device which accurately electrically connects a conducting layer to an internal wired layer on a silicon substrate and where the wired layer has a line width which is the minimally attainable width utilizing present lithographic etching process techniques.
2. Information Disclosure Statement
Generally, in manufacturing an integrated circuit semiconductor device, in order to electrically connect a conducting layer through an insulating layer to an internal wired layer deposited on a substrate, a portion of the insulating layer formed on the internal wired layer should be precisely etched to define a contact region which exposes only the surface of the underlying internal wired layer. Therefore, the contact region for forming a contact hole through which an electrical connection is accomplished should be retained by precisely arranging a contact mask at a predetermined position in accordance with design rules for the semiconductor device. Furthermore, the width of the underlying internal wired layer to which the conducting layer is to be connected should be greater than the bore/width of the contact hole considering the minimum misalignment tolerance required for the mask patterning process for the internal wired layer and the critical dimension loss which occurs during the lithographic etching process. If the width of the contact hole is either larger than that of the internal wired layer or is the same as that of the internal wired layer, and the contact mask arranged on the insulating layer for forming the contact hole is misaligned, the resulting etched contact hole is also misaligned which exposes unintended portions of the underlying substrate. Therefore when a conducting layer is deposited on the resulting structure including the exposed portion of the substrate, the conducting layer is undesirably connected through the misaligned contact hole to the exposed portion of the substrate, so that the semiconductor device fails to operate as designed.
Therefore, according to the prior art, in order to form a contact hole for connecting a conducting layer through the contact hole to the underlying internal wired layer formed on the substrate, the width of the wired layer should be larger than that of the contact hole, so that the problems set forth above can be avoided or at least minimized. However upon increasing the width of the wired layer, the cell width of the resulting semiconductor device is undesirably increased so that integrity of semiconductor device decreases.
Accordingly, it is an object of the present invention to solve the problems set forth above in the prior art, and to provide a connection device in a semiconductor device by providing an etch stop layer on an insulating layer at a position overlapping with one side of the underlying internal wired layer, and forming a contact hole in the insulating layer in a position from the portion of the etch stop layer to the portion of the wired layer, and depositing a conducting layer on the resulting structure to electrically connect the conducting layer through the contact hole to the wired layer, so that an electrical connection therebetween is desirably accomplished, although the resulting contact hole is misaligned during the contact mask patterning process, and a method for manufacturing the same.
According to the present invention the etching process for forming the contact hole prevents the underlying substrate from being exposed by the formation process of the contact hole so that the conducting layer to be deposited is desirably connected through even a misaligned contact hole to the wired layer having a line width which is the minimally attainable width utilizing present lithographic etching process techniques formed on the substrate. Further, because of the use of the minimally attainable width of the wired layer the area of the resulting semiconductor can be decreased so that the integrity thereof increases.
The preceding objects should be construed as merely presenting a few of the more pertinent features and applications of the invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or modifying the invention within the scope of the disclosure. Accordingly, other objects and a fuller understanding of the invention may be had by referring to both the summary of the invention and the detailed description, below, which describe the preferred embodiment in addition to the scope of the invention defined by the claims considered in conjunction with the accompanying drawings.